Add versions API in doc
Add versions API in doc

Currnt docs lacks version API in it. This patch adds the API.

Change-Id: Ib486eedaf99cc1415733d167ca5c6fa4e5b1574d

ekcs/congress,ramineni/my_congress,openstack/congress,openstack/congress,ramineni/my_congress,ramineni/my_congress,ekcs/congress,ekcs/congress,ramineni/my_congress,ekcs/congress